Re: It'll just make you want something better...
mdocod wrote:
maltmoose wrote:
I'd like to see the evidence that 75mm vs 300 will give a comparable or better image, even 200 or 150mm vs 75 for that matter.
I wish it were true as i would be using my 25mm instead of a 100mm telephoto..
I don't really see how the 25mm instead of 100mm applies here....
I'm talking about a very specific prime lens, known to be one of the sharpest lenses ever made being used as an alternative to to what is essentially the "kit" X-300mm small aperture telephoto option from olympus.
In this very specific comparison, in conditions that push the 75-300 into requiring higher iso or under-exposure and electronic shutter to produce acceptable results, the 75mm prime is apt to produce an image that can be cropped to a very similar "effective" resolve, and in some cases will likely out-resolve the zoom lens.
Comparing a $550 "kit" zoom to a $899 prime lens somehow seems disingenuous. These are two different animals. It's like comparing a BMW 3 series against a Dodge Caravan. one is fairly exotic, the other is built for utility.
Lab tests at imaging resources reveal similar results. In many conditions, the 75mm prime "resolves" about double the effective resolution compared to the 75-300....
Interesting...
Here is what Imaging Resource had to say about the 75-300
"Sharpness
The 75-300mm ƒ/4.8-6.7 II offers excellent results in the wider end of its focal length spectrum. Even used wide open at 75mm and ƒ/4.8, the lens produces tack-sharp images from corner to corner (this is also true at 100mm and ƒ/5.1). Stopping down at either of these focal lengths doesn't produce any tangible increase in sharpness.
At 150mm and above, resolution suffers a bit. Wide open at ƒ/5.6 and 150mm, the central area of the frame is nice and sharp and we note some corner softness in the extreme corners, but stopping down to ƒ/8 or greater doesn't actually improve the corners - rather, the center degrades a bit to match the corners.
At 200mm and 300mm, the lens offers above-average performance for sharpness; the center is decently sharp, but the corners are significantly soft. Stopping down to ƒ/11 does help at the 200mm setting, but at 300mm setting, there's no significant improvement.
Diffraction limiting sets in at ƒ/11, though the results at the shorter focal lengths aren't immediately obvious until ƒ/16 or ƒ/22, where we note very soft results across the frame "
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The takeaway, from my experience with both of these lenses, is that the 75mm prime can do a lot of the work that the 75-300 can through post-cropping due to extraordinary sharpness and reduced noise from being able to operate at lower iso or higher exposure. On the other hand, the 75-300 can't step in and do the work that the 75mm prime can.
This may seem counter-intuitive, but that is my experience, take it or leave it.
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shinndigg
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